Zheliznyak , I., Voitenko , S. and Karunna , T. 2019. Possibility of increasing dairy productivity of cows of Ukrainian black-spotted dairy breed due to breeding and technological factors . Bulletin of Sumy National Agrarian University. The series: Livestock. 4(39) (Dec. 2019), 49-56. DOI:https://doi.org/10.32845/bsnau.lvst.2019.4.7.